摘要：设计制作了一种采用双晶片压电陶瓷结构的棒板结合式压电驱动器。和参考文献中的驱动器不同,其两个压电陶瓷片分别粘接在青铜定子的上下两侧。定子上的金属圆柱体被用来放大振动的横向位移,并对金属棒状的转子进行激振,使其旋转。利用有限元分析(FEA)对定子进行了分析,发现在同样的驱动模式下,与传统的单片陶瓷片驱动器相比,该驱动器可以提供更多的横向和纵向的振动位移,大约提高25%左右。这种新结构也可避免不同振动模式之间的模态耦合现象,并产生理想的振动模态,以提高驱动器的运行稳定性。实验表明,驱动器在25Vo-p低电压下可以提供512r/min的转速,而单片陶瓷驱动器在该电压下不能工作。这种压电驱动器可以经过优化和调整来满足不同的实际应用,如精确定位仪器,生物工程和光聚焦系统等。

摘要：As a core part of subsea production systems,subsea control modules(SCMs)are costly,difficult,and expensive to install and inconvenient to use in underwater ***,performance and function tests must be carried out before launching *** study developed a testing device and an SCM test by investigating SCMs and their *** testing device includes four parts:a hydraulic station,an SCM test stand,a signal generating device,and an electronic test ***,the basic indices of the testing device were determined from the performance and working parameters of the ***,the design scheme of the testing device for the SCM was tentatively proposed,and each testing device was ***,a practical measurement of the SCM,in combination with the hydraulic station,SCM test stand,signal generator,electronic unit,and highpressure water tank,was carried out according to the test *** measurement mainly involved equipment inspection before testing and an experimental test for the *** validity and feasibility of the testing device and method were simultaneously verified through an association test.

摘要：This paper describes the design for testability （DFT） challenges and techniques of Godson-3 microprocessor, which is a scalable multicore processor based on the scalable mesh of crossbar （SMOC） on-chip network and targets high-end applications. Advanced techniques are adopted to make the DFT design scalable and achieve low-power and low-cost test with limited IO resources. To achieve a scalable and flexible test access, a highly elaborate test access mechanism （TAM） is implemented to support multiple test instructions and test modes. Taking advantage of multiple identical cores embedding in the processor, scan partition and on-chip comparisons are employed to reduce test power and test time. Test compression technique is also utilized to decrease test time. To further reduce test power, clock controlling logics are designed with ability to turn off clocks of non-testing partitions. In addition, scan collars of CACHEs are designed to perform functional test with low-speed ATE for speed-binning purposes, which poses low complexity and has good correlation results.

摘要：整合重构的基本思想和物理设计的基本技术,提出了物理重构的概念.它是对软件物理结构的再设计,目的是在不改变软件外在行为的前提下,调整软件组织结构,从而提高软件的开发效率和可维护性等.在此基础上,提出用"识别-重构-评估"的迭代过程来实施物理重构,并介绍了常用的物理重构方法.实例研究表明,物理重构能够有效地优化系统的物理结构,使开发者从多个角度持续改善软件质量.

摘要：为了实现根茬的挖掘、捡拾、根土分离与放铺等联合收获作业,研制了一种偏置式挖掘铲刀和三辊机构。通过分析偏置式挖掘铲刀的挖掘特性,以及三辊机构的运动学特性,确定了工作部件的结构参数及运动参数。田间试验表明,偏置式挖掘铲刀挖掘根茬效果好,三辊机构具有较好的捡拾、根土分离和放铺能力,根茬收获机的根茬起挖率、捡拾率和放铺率均大于90%,满足设计和使用要求。

摘要：设计了一种针对闭环加速度计的新型自检测结构.详细描述了这种基于电荷注入的自检测功能的原理.针对时分反馈闭环加速度计,从理论上推导了加速度计输出与自检测电压之间的关系,并利用Matlab/Simulink模型进行了验证.基于0.35μm高压CMOS工艺,设计了整个读出电路.测试结果显示,在自检测模式下,输出对自检测电压的灵敏度是0.3 V/V.

摘要：该文推导卫星编队飞行的一般相对运动动力学模型,研究将指数趋近律滑模控制与神经网络控制相结合的卫星编队飞行控制方法,设计一种径向基神经网络参数调节器.实时调节指数趋近律的参数,从而取得滑动面的趋近速度和燃料消耗的最优平衡.采用指数趋近律滑模控制法,用饱和函数代替可能产生高频切换信号的开关函数,有效地削弱了滑模控制的抖动.二阶滑模控制结构保证了卫星编队的高精度控制.仿真结果表明了这一控制方法的有效性.

摘要：为了解决目前结构性演化测试主要集中于面向语句、分支等覆盖标准,缺乏面向路径覆盖标准的问题,提出了基于相似性度量的适应值函数构造方法,以用于生成覆盖指定路径的测试用例.首先给出适应值函数构造基本模型,即利用测试数据的真实执行轨迹来评估它相对于指定路径的适应值.该模型的核心在于度量执行轨迹与指定路径之间的相似度,为此给出了3种不同的相似度度量算法.该模型可以完全自动化地为每一条目标路径构造出特定的适应值函数.实验结果表明,相对于其他路径测试方法,该方法在针对复杂路径的情况下具有一定的优势.此外,实验结果还指出了该方法的适用性范围和局限所在.

摘要：在无线传感器网络体系结构中,MAC(medium access control)协议是保证网络高效通信的重要协议.无线传感器网络有着与传统无线网络明显不同的性能特点和技术要求,传统无线网络MAC协议无法应用于传感器网络,各种针对特定传感器网络特点的MAC协议相继提出.归纳无线传感器网络MAC协议的设计原则和分类方法,分析当前典型的各类MAC协议的主要机制,详细比较这些协议的特点、性能差异和应用范围.最后总结无线传感器网络MAC协议的研究现状,指出未来的研究重点.

摘要：The building information model/modeling （BIM） technology is currently applied in a broad range of applications and research for facility management, while the BIM-based mobile FM is difficult owing to various factors and environments. For example, the mobile applications usually require frequent cross-equipment compatibility. This paper proposes a reasonable BIM-based FM cross-platform framework and develops a mobile application on the basis of an existing BIM-based FM system. The developed mobile application is applied in a case study of a metro station project in Guangzhou to verify its effectiveness in FM practice. It helps maintenance staff in viewing BIMs, accessing related information, and updating maintenance records in a unique platform. The test results demonstrate that the proposed BIM-based cross-platform framework meet the FM application requirements and supports the extension of FM functions.